Evaluation of Safety and Efficacy of Traction, Closed Reduction, and Subsequent Hip Fixation in Hilgenreiner Brace in Patients with Severe Forms of Hip Developmental Dysplasia
Table 2
Basic Severin classification system.
Class
X-ray appearance
Angle of the central margin
I
Normal
15°–25°
II
Medium deformity of the femoral head, neck of the femur, or the acetabulum
15°–25°
III
Dysplasia without subluxation
<15° (6 to 13 years) <20° (>14 years)
IV
Subluxation
>0°
V
The femoral head is articulated with a pseudoacetabulum in the proximal part of the original acetabulum